Originally indicated as an alarm alert in a 1990s US publication, this circuit can be used as a shield to control a strobe lamp. The sensor is a optocoupler with LDR.
Found in a 1980s telecommunications documentation, this balanced modulator circuit uses...
This circuit was found in a 90’s 303 Circuits. The components are from the period and the heating...
This simple receiver that works with only 1.5 V, was found in a 1987 documentation. The integrated...